PONE-D-21-08345

Decreased Continuous Sitting Time Increases Heart Rate Variability in Patients with Cardiovascular Risk Factors

PLOS ONE

Dear Dr. Natsuki Nakayama,

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Reviewers' comments:

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Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

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Reviewer #1: Yes

Reviewer #2: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Dear the authors of the manuscript entitled "Decreased Continuous Sitting Time Increases Heart Rate Variability in Patients with Cardiovascular Risk Factors"

Thank you very much for writing this manuscript which describes a valuable experiment discussing the positive effects of decreased sitting behavior on the outcomes of patients with cardiovascular risk factors

I have 2 points to mention here:

1. There was no mention on echocardiographic assessment for the patients included, which I think is relevant to the outcomes for these patients

2. The discussion part is deviated from the main theme of the study, please elaborate more about the results you obtained in the experiment ie(HF HRV and change in sitting behavior)

Otherwise I have no concerns about it

Thank you

Reviewer #2: This was an interesting study explaining the association between high-frequency heart rate variability and daytime sitting time among patients with cardiovascular risk factors. However, the authors should consider addressing the following:

1. The authors should provider how they arrived at the sample (53) of participants that participated in their study. Were the participants selected at random?

2. Under the Ethical consideration (page 7, lines 123-127) the authors need to specify the institutions that granted the ethical approval(s) for their study and the corresponding reference numbers. The authors are affiliated to five (5) institutions and this needs to be specified.

3. On page 8, line 151, the authors should replace the word “deceased” with “decreased”.

4. On page 13, the authors should consider providing a limitation of the methods used in their study. The authors also mentioned on lines 215 - 216 that “Patients who participated in this trial suffered from mild hypertension and/or stable angina pectoris.” The authors need to specify whether or not they conducted a trial and if so which type? In addition, was the trial registered? and was the protocol number provided anywhere in the methods?

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Reviewer #1: Yes: salah eldien Altarabsheh

Reviewer #2: No

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Decreased Continuous Sitting Time Increases Heart Rate Variability in Patients with Cardiovascular Risk Factors

PONE-D-21-08345R1

Dear Dr. Natsuki Nakayama,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Sharon Mary Brownie

Academic Editor

PLOS ONE

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Dear the authors

I want to thank you for revising the manuscript and taking in consideration the reviewers comments

I have no concerns

Reviewer #2: The authors have addressed my previous comments and the manuscript has been strengthened further.

However, as a discretionary comment, on page 14, lines 229-230, the sentence that reads "Despite these findings, the present study has some limitations. Patients who participated in this analysis had mild hypertension and/or stable angina pectoris." I suggest the word 'analysis' should be substituted with 'study'. This is because the patients participated in the study and not the analysis.

Otherwise, all my comments have been duly addressed.

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Salah Eldien altarabsheh

Reviewer #2: No